Recognise any similarities in the latest proposal from the Australian Building Code?
The references to FED limited to 0.3 seems to be copying our seriously flawed C/VM2. The remainder of the document seems to have more in common with the Fiji National Building Code.
Aussie has been working on a VM for some years. Things move slowly there as each state has to agree and there are politics involved. In my experience of fire engineering in Oz, it seems to be less engineering and selling a snow job to the building certifier using pretty pictures and “trust me a I am an engineer” and this won’t help that one, but might help with consistent start and finish criteria if not any dodgy work in the middle.
Interesting, from teh way I read it, they have visibility (in all cases) + FED (thermal) as their criteria, and FED(thermal) only as the RC. FED(CO) is not required at all. It fluffs around small rooms and dead ends by referring to the DTS “acceptable solution” for these areas. The DTS values in Oz are less than herewith no recognition of smoke detection or sprinklers (although I haven’t been through the latest NCC). DEOP = 20m in an office as I recall, even with a type 7.
I have concerns with the NZ FED(CO) = 0.3 for day to day safety as it equates to a ~10% incapacitation rate in the standard population and more with elderly or the young. It does however at least recognize the effect of cold-ish smoke remote from the fire which is still toxic.
FED(thermal) only is (in my opinion) a mistake by the ozzies as we all have buildings that fail FED(CO) eventually but come no where near FED(thermal). I had one project that has thermal latches on windows into an apartment atrium where the apartment fire only gets to ~45 degrees at the latch which will never activate. Fore FED(thermal) you would have infinite RC time, although I would want to be somewhere else I think when I looked at the top floor conditions.
They have extended the VM scenarios against NZ with some specific structural ones. These are are not in our VM as they are covered by other NZBC clauses - particularly structural collapse and disproportionate collapse sit under NZBC B1
One of the (several) issues with our VM is that it is “deemed to comply” and hence we get buildings that are legally safe dangerous buildings. Examples such as retirement villages with no fire separations (as there is no property protection required as they are one title. Apparently granny can move a 1.2m/s through thick, choking smoke at 3am (unlike Jin’s tests of students) and doesn’t take her hearing aids out at night so can hear the alarm, because if she doesn’t go, it will save the family the cost of a cremation.
It doesn’t appear that Australia have made it a Deemed to Satisfy (DTS) solution however a VM is defined in the document as a way of demonstrating the performance criteria is met so may not be any practical difference. They should do (as we should do) is treat it as a design guide only